Education · Tier 1

· Last Reviewed May 15, 2026· PSI Editorial Board· Independent

What Is Peptide Therapy?

The universal awareness reference for peptide therapy anchored in FDA prescribing information and the PSI four-tier evidence framework.

Peptide therapy uses short chains of amino acids as signaling molecules to influence biological pathways.

The FDA-approved peptide drug class spans multiple indications.

Compounded peptide preparations operate under AMA Code 1.1.5 framework.

FDA Approved

Multi-Indication Class

FDA-approved peptide drugs span GLP-1 receptor agonists, anabolic osteoporosis peptides, growth hormone secretagogue, and sexual health peptides

AMA 1.1.5

Compounded Framework

Compounded peptide preparations operate under AMA Code of Medical Ethics 1.1.5 framework with documented risk-benefit assessment

Four Tiers

Evidence Framework

PSI four-tier evidence framework: L1 preclinical, L2 animal studies, L3 human trials, L4 FDA-approved

Physician

Clinical Practice

Peptide therapy clinical practice is physician-directed with FDA prescribing information and AMA Code 1.1.5 framework

Quick Answer

Peptide therapy uses short chains of amino acids as signaling molecules. Peptides influence biological pathways including metabolic, anabolic, immune, and signaling functions. Peptide therapy clinical practice is physician-directed.

The FDA-approved peptide drug class spans multiple indications. GLP-1 receptor agonists include Semaglutide (Wegovy NDA 215256, Ozempic NDA 209637) and Tirzepatide (Zepbound NDA 217806, Mounjaro NDA 215866). These are FDA-approved for chronic weight management and type 2 diabetes. The anabolic osteoporosis peptide class includes Teriparatide (Forteo NDA 021318), abaloparatide (Tymlos NDA 208743), and romosozumab (Evenity NDA 761062 with cardiovascular boxed warning). Tesamorelin Egrifta (NDA 022505) treats HIV-associated lipodystrophy. Vyleesi bremelanotide (NDA 210557) treats HSDD in premenopausal women.

Compounded peptide preparations operate under the FDA Compounding Quality Act of 2013 without FDA pre-market approval. Compounded preparations operate through 503A pharmacies or 503B outsourcing facilities. Compounded peptide protocols operate under AMA Code of Medical Ethics 1.1.5 framework. The framework requires documented risk-benefit assessment, FDA-approved alternatives considered, monitoring requirements, and patient understanding. See The Compounding Pharmacy System for the regulatory framework.

The PSI four-tier evidence framework provides transparent classification across compounds. L1 preclinical applies to in vitro and mechanistic evidence. L2 animal studies applies to rodent and other animal model evidence. L3 human trials applies to Phase 1, Phase 2, and Phase 3 evidence including international approvals. L4 FDA-approved applies to compounds with completed FDA pre-market review. See Evidence Levels Explained for the methodology.

The four-stage monitoring cadence applies across the class. Baseline at week 0. Early follow-up at week 4 to 8. Stabilization at month 3. Maintenance at month 6 with annual continuation thereafter. The physician determines monitoring frequency per indication and FDA label.

Peptide therapy clinical practice requires physician evaluation. PSI does not provide personalized clinical recommendations. Discuss specific peptide therapy with your prescribing physician.

FDA-approved peptide classes include GLP-1 receptor agonists, PTH analogs, sclerostin antibody, growth hormone secretagogue, and melanocortin. Compounded preparations operate under the FDA Compounding Quality Act of 2013. Physician protocols follow AMA Code 1.1.5. The PSI four-tier evidence framework provides transparent classification. This page is conceptual education only.

PEPTIDE THERAPY OVERVIEW

At a Glance: What Is Peptide Therapy

Framework Element	Subtitle	Animal Evidence	Human Evidence	Application
Peptides as signaling molecules	Short amino acid chains influencing biological pathways	—	Strong	Peptides typically contain fewer than 50 amino acids. They signal cellular processes through receptor binding including GLP-1 receptor, parathyroid hormone receptor, and others
FDA-approved peptide drug class	Multi-indication class with completed FDA review	—	Strong	FDA-approved class spans GLP-1 receptor agonists, anabolic osteoporosis peptides, sclerostin antibody, growth hormone secretagogue, and sexual health peptides
GLP-1 receptor agonist class	Wegovy, Ozempic, Zepbound, Mounjaro per FDA labels	—	Strong	Semaglutide (Wegovy NDA 215256, Ozempic NDA 209637) and tirzepatide (Zepbound NDA 217806, Mounjaro NDA 215866). SELECT 2023 demonstrated CV benefit
Anabolic osteoporosis peptide class	Forteo, Tymlos, Evenity per FDA labels	—	Strong	Teriparatide (NDA 021318), abaloparatide (NDA 208743), romosozumab (NDA 761062 with CV boxed warning). Cumulative lifetime maximums for PTH analogs
Compounded peptide preparations	FDA Compounding Quality Act of 2013 framework	—	Moderate	503A pharmacies and 503B outsourcing facilities. Compounded protocols operate under AMA Code of Medical Ethics 1.1.5 framework
AMA Code 1.1.5 prescribing framework	Off-label and compounded prescribing ethics	—	Moderate	Documented risk-benefit assessment, FDA-approved alternatives considered, monitoring requirements, and patient understanding through informed consent
PSI four-tier evidence framework	L1 preclinical to L4 FDA-approved	—	Strong	Visitor labels: FDA Approved (L4), Human Trials (L3), Animal Studies (L2), Preclinical (L1). Every PSI claim links to PubMed-indexed primary sources
Physician-directed clinical practice	Dosing, route, schedule, and protocol per FDA label	—	Strong	Peptide therapy clinical practice is physician-directed. PSI does not provide personalized clinical recommendations. Discuss with prescribing physician

Six Things You Need to Know About Peptide Therapy

This page covers peptide therapy at the universal-awareness level. Section one covers peptide biology and signaling mechanisms. Section two covers the FDA-approved peptide drug class across indications. Section three covers compounded peptide preparations and AMA Code of Medical Ethics 1.1.5 framework. Section four covers the PSI four-tier evidence framework. This page is conceptual education only.

Peptides Are Short Amino Acid Chains That Signal Cellular Processes

Peptides are short chains of amino acids that function as signaling molecules in the body. Peptides influence biological pathways through receptor binding. Examples include GLP-1 receptor, parathyroid hormone receptor, and growth hormone secretagogue receptor pathways.

Peptides are short chains of amino acids typically containing fewer than 50 amino acids. The amino acids are linked by peptide bonds creating chains that function as signaling molecules. Peptides bind to specific cellular receptors triggering downstream signaling cascades. The GLP-1 receptor agonist class binds the GLP-1 receptor expressed in pancreatic beta cells, gastric tissue, and central nervous system locations. Examples include semaglutide and tirzepatide. The parathyroid hormone receptor pathway responds to teriparatide and abaloparatide with bone formation effects. The Wnt signaling pathway responds to romosozumab via sclerostin antibody mechanism. The growth hormone secretagogue receptor responds to Tesamorelin Egrifta in HIV-associated lipodystrophy context. The melanocortin receptor responds to bremelanotide in HSDD context. Peptide therapy operates through these established receptor signaling pathways. The mechanisms are documented in PubMed-indexed peer-reviewed primary sources across multiple decades of research.

The FDA-Approved Peptide Drug Class Spans Multiple Indications

The FDA-approved peptide drug class includes GLP-1 receptor agonists for chronic weight management and type 2 diabetes, anabolic osteoporosis peptides for postmenopausal osteoporosis with high fracture risk, growth hormone secretagogue for HIV-associated lipodystrophy, and sexual health peptides for HSDD in premenopausal women.

The FDA-approved peptide drug class operates under FDA prescribing information with completed FDA pre-market review per 21 CFR 314. The GLP-1 receptor agonist class includes semaglutide (Wegovy NDA 215256 for chronic weight management, Ozempic NDA 209637 for type 2 diabetes), tirzepatide (Zepbound NDA 217806 for chronic weight management, Mounjaro NDA 215866 for type 2 diabetes), and liraglutide (Saxenda for weight management, Victoza for type 2 diabetes). SELECT 2023 NEJM (Lincoff et al.) demonstrated cardiovascular benefit. SUSTAIN-6 NEJM 2016 (Marso et al.) and SURMOUNT-1 NEJM 2022 (Jastreboff et al.) anchored additional approvals. The anabolic osteoporosis peptide class includes teriparatide (Forteo NDA 021318), abaloparatide (Tymlos NDA 208743), and romosozumab (Evenity NDA 761062 with cardiovascular boxed warning). VERT NEJM 2001 (Neer et al.), ACTIVE JAMA 2016 (Miller et al.), FRAME NEJM 2016 (Cosman et al.), and ARCH NEJM 2017 (Saag et al.) anchored these approvals. Tesamorelin Egrifta (NDA 022505) treats HIV-associated lipodystrophy. Bremelanotide Vyleesi (NDA 210557) treats HSDD in premenopausal women. The class continues to expand with new FDA approvals.

Compounded Peptide Preparations Operate Under AMA Code 1.1.5 Framework

Compounded peptide preparations operate under the FDA Compounding Quality Act of 2013 (Drug Quality and Security Act). Compounded preparations operate through two pathways. 503A traditional compounding pharmacies prepare patient-specific preparations per physician prescription. 503B outsourcing facilities prepare larger batches under FDA registration with adherence to current Good Manufacturing Practice standards. The Pharmacy Compounding Accreditation Board (PCAB) accredits compounding pharmacies meeting USP General Chapter 797 sterile compounding standards and USP General Chapter 800 hazardous drug handling standards. State pharmacy boards provide oversight. AMA Code of Medical Ethics 1.1.5 (Off-Label and Investigational Use of Pharmaceuticals) governs the prescribing decision. The framework requires documented risk-benefit assessment for the specific patient context, FDA-approved alternatives considered per indication, monitoring requirements including baseline labs and follow-up cadence, and patient understanding through informed consent acknowledgment. AMA Code 2.1.1 establishes the broader informed consent framework. Examples of compounded peptides include thymosin alpha-1, BPC-157, sermorelin, and others. See [The Compounding Pharmacy System](/education/the-compounding-pharmacy-system) for the regulatory framework.

The PSI Four-Tier Evidence Framework Provides Transparent Classification

PSI uses a four-tier evidence framework distinguishing L1 preclinical, L2 animal studies, L3 human trials, and L4 FDA-approved compounds. Visitor-facing labels are FDA Approved, Human Trials, Animal Studies, and Preclinical.

The PSI four-tier evidence framework supports transparent claim communication across compounds with varying evidence quality. L1 preclinical applies to compounds with primarily in vitro studies, mechanistic biology, or computational modeling evidence. L2 animal studies applies to compounds with rodent and other animal model evidence without human trial data. L3 human trials applies to compounds with Phase 1, Phase 2, and Phase 3 evidence including international approvals. L4 FDA-approved applies to compounds with completed US FDA pre-market review and approved labels. The framework integrates with standard methodology including GRADE evidence quality assessment, Cochrane systematic review methodology, USPSTF grading framework, AHRQ evidence-based practice center methodology, FDA Drug Approval Process per 21 CFR 314, and ICH E6 Good Clinical Practice. Every compound on PSI declares one locked evidence level traceable to PubMed-indexed peer-reviewed primary sources. See [Evidence Levels Explained](/education/evidence-levels-explained) for the methodology. See [How to Read PubMed](/education/how-to-read-pubmed) for primary-source verification.

The Four-Stage Monitoring Cadence Applies Across the Class

The four-stage monitoring cadence applies across FDA-approved and compounded peptide therapy. Baseline at week 0. Early follow-up at week 4 to 8. Stabilization at month 3. Maintenance at month 6 with annual continuation thereafter.

The four-stage monitoring cadence supports systematic peptide therapy management. Stage 1 baseline at week 0 establishes the indication-appropriate marker panel including IGF-1, hemoglobin A1c, lipid panel, bone turnover markers, mineral metabolism markers, CBC, comprehensive metabolic panel, lymphocyte subsets, or lipase per peptide class and indication. Stage 2 early follow-up at week 4 to 8 tracks tolerability and side effect emergence. The window captures GLP-1 receptor agonist gastrointestinal tolerability assessment. Stage 3 stabilization at month 3 captures steady-state pharmacologic response. Stage 4 maintenance at month 6 with annual continuation thereafter applies the full panel re-check. The framework anchors physician-directed peptide therapy across the FDA-approved and compounded class. Indication-specific markers re-checked at each stage depend on peptide class per FDA prescribing information or AMA Code 1.1.5 documentation. See [Biomarker Interpretation](/education/biomarker-interpretation) for marker-specific framework.

Peptide Therapy Clinical Practice Is Physician-Directed

Peptide therapy clinical practice is physician-directed. The physician determines all dosing, route, schedule, and protocol design decisions per FDA prescribing information for FDA-approved peptides and AMA Code 1.1.5 framework for compounded preparations.

Peptide therapy clinical practice operates under physician direction. The physician determines indication-appropriate dosing per FDA label range for FDA-approved peptides. The physician determines route per FDA prescribing information (subcutaneous, intramuscular, or intravenous depending on peptide class). The physician determines schedule (weekly, daily, monthly, or on-demand per FDA label). The physician determines the appropriate clinical context including indication match, comorbidity assessment, concurrent medication review, and contraindication evaluation. For patient-administered injections, the physician or pharmacist provides administration instruction. The physician monitors for adverse events through clinical follow-up and FDA MedWatch reporting for serious events. AMA Code 1.1.5 framework applies for off-label and compounded prescribing decisions with documented risk-benefit assessment. Specialty coordination spans primary care, endocrinology, weight medicine, rheumatology, sports medicine, immunology, infectious disease, women's health, men's health, and cardiology for cardiovascular boxed warning contexts. The PSI physician directory provides verified physicians applying FDA prescribing information and AMA Code 1.1.5 framework. PSI provides conceptual education only.

Peptides versus steroids: distinct molecular classes with distinct clinical frameworks

Signaling peptides operate through receptor binding; anabolic steroids operate through hormone replacement

Peptides and anabolic steroids represent distinct molecular classes with distinct clinical frameworks. Peptides are short chains of amino acids that function as signaling molecules. Peptides bind specific cellular receptors triggering downstream signaling cascades. The GLP-1 receptor agonist class binds the GLP-1 receptor with effects on insulin secretion, gastric emptying, and central satiety. The parathyroid hormone receptor pathway responds to teriparatide and abaloparatide with bone formation effects. The growth hormone secretagogue receptor responds to Tesamorelin Egrifta.

Anabolic steroids are synthetic hormones structurally related to testosterone. Anabolic steroids directly replace or amplify hormone levels rather than signaling endogenous physiologic processes. Anabolic steroids operate under different regulatory frameworks including Schedule III controlled substance classification under the Controlled Substances Act in the United States. Anabolic steroid clinical use is restricted to specific FDA-approved indications including hypogonadism, severe weight loss in HIV-associated wasting, and other limited contexts.

FDA-approved peptide drugs operate under FDA prescribing information per 21 CFR 314. Compounded peptide preparations operate under FDA Compounding Quality Act of 2013 with AMA Code of Medical Ethics 1.1.5 framework. Both peptide categories operate within the legitimate clinical practice framework with physician-directed protocols. PSI documents peptide therapy. PSI does not document anabolic steroid use.

FDA-approved peptide class versus compounded peptide preparations

Distinct regulatory frameworks with distinct evidence requirements

The FDA-approved peptide drug class operates under FDA pre-market review per 21 CFR 314 with FDA prescribing information specifying indication, dosing, route, schedule, and monitoring. FDA approval requires demonstration of safety and efficacy through Phase 1 first-in-human safety trials, Phase 2 dose-finding trials, and Phase 3 pivotal efficacy and safety trials. The trial program operates under ICH E6 Good Clinical Practice with CONSORT reporting standards for randomized trials. Post-marketing surveillance through FDA MedWatch supports ongoing safety signal monitoring. Examples include Wegovy semaglutide for chronic weight management and Forteo teriparatide for postmenopausal osteoporosis.

Compounded peptide preparations operate under the FDA Compounding Quality Act of 2013 (Drug Quality and Security Act) without FDA pre-market approval. Compounded preparations operate through 503A traditional compounding pharmacies preparing patient-specific preparations or 503B outsourcing facilities preparing larger batches under FDA registration. The Pharmacy Compounding Accreditation Board accredits pharmacies meeting USP General Chapter 797 sterile compounding standards. State pharmacy boards provide oversight. Examples include compounded thymosin alpha-1, BPC-157, sermorelin, and others.

Compounded peptide prescribing decisions operate under AMA Code of Medical Ethics 1.1.5 framework. The framework requires documented risk-benefit assessment for the specific patient context, FDA-approved alternatives considered per indication, monitoring requirements including baseline labs and follow-up cadence, and patient understanding through informed consent acknowledgment. AMA Code 2.1.1 establishes the broader informed consent framework. The two categories operate under distinct regulatory frameworks with distinct evidence requirements. PSI documents both categories with transparent four-tier evidence classification.

The PSI four-tier evidence framework spans the peptide therapy landscape

L1 preclinical to L4 FDA-approved with visitor-facing labels

The PSI four-tier evidence framework provides transparent classification across compounds with varying evidence quality. L1 preclinical applies to compounds with primarily in vitro studies, mechanistic biology, or computational modeling evidence. Examples include early-stage research peptides without published Phase 1 trial data. L2 animal studies applies to compounds with rodent and other animal model evidence without human trial data. Examples include the Sikiric laboratory BPC-157 research program with rodent tendon healing and gastrointestinal cytoprotection model evidence.

L3 human trials applies to compounds with Phase 1, Phase 2, and Phase 3 evidence including international approvals. Examples include thymosin alpha-1 with international Zadaxin approval in approximately 35 countries supported by hepatitis B and hepatitis C Phase 3 clinical evidence. L4 FDA-approved applies to compounds with completed US FDA pre-market review and approved labels. Examples include semaglutide, tirzepatide, teriparatide, abaloparatide, romosozumab, Tesamorelin, and bremelanotide.

Visitor-facing labels translate the framework: FDA Approved (L4), Human Trials (L3), Animal Studies (L2), and Preclinical (L1). Every compound on PSI declares one locked evidence level traceable to PubMed-indexed peer-reviewed primary sources documented in the data layer. The framework integrates with standard methodology including GRADE evidence quality assessment, Cochrane systematic review methodology, USPSTF grading, AHRQ evidence-based practice center methodology, FDA Drug Approval Process per 21 CFR 314, and ICH E6 Good Clinical Practice. See Evidence Levels Explained for the methodology.

Research Suggests

Direction

Peptide therapy uses short chains of amino acids as signaling molecules. The FDA-approved class spans multiple indications. Compounded preparations operate under AMA Code 1.1.5 framework. The PSI four-tier evidence framework provides transparent classification.

Peptides operate through receptor binding triggering downstream signaling cascades including GLP-1 receptor, parathyroid hormone receptor, growth hormone secretagogue receptor, Wnt signaling via sclerostin antibody, and melanocortin receptor pathways. The FDA-approved class includes GLP-1 receptor agonists (Wegovy, Ozempic, Zepbound, Mounjaro), anabolic osteoporosis peptides (Forteo, Tymlos, Evenity with cardiovascular boxed warning), Tesamorelin Egrifta for HIV-associated lipodystrophy, and Vyleesi bremelanotide for HSDD in premenopausal women. Cardiovascular outcomes evidence anchors many compounds including SELECT 2023 NEJM and SUSTAIN-6 NEJM 2016. Compounded preparations operate under FDA Compounding Quality Act of 2013 through 503A and 503B pathways with AMA Code 1.1.5 prescribing framework. The four-stage monitoring cadence applies across the class.

Strongest evidence

FDA-approved peptide drugs anchored in Phase 3 trial evidence provide the strongest evidence framework across the peptide therapy landscape.

FDA-approved peptide drugs operate under FDA prescribing information per 21 CFR 314 with completed FDA pre-market review. Phase 3 trial evidence anchoring includes SELECT 2023 NEJM (Lincoff et al. semaglutide cardiovascular outcomes), SUSTAIN-6 NEJM 2016 (Marso et al. semaglutide cardiovascular outcomes in T2D), SURMOUNT-1 NEJM 2022 (Jastreboff et al. tirzepatide weight management), LEADER NEJM 2016 (Marso et al. liraglutide cardiovascular outcomes), VERT NEJM 2001 (Neer et al. teriparatide fracture reduction), ACTIVE JAMA 2016 (Miller et al. abaloparatide fracture reduction), FRAME NEJM 2016 (Cosman et al. romosozumab fracture reduction), and ARCH NEJM 2017 (Saag et al. romosozumab vs alendronate with cardiovascular boxed warning). Society Clinical Practice Guidelines anchor clinical application including AACE/ACE 2020 Postmenopausal Osteoporosis CPG, Endocrine Society 2019 CPG, ADA 2024 Standards of Care, and AACE 2019 Adult GHD CPG. ICH E6 Good Clinical Practice and CONSORT reporting standards apply across the FDA-approved class.

Limitations

Compounded peptide preparations operate outside FDA pre-market approval. The evidence base varies substantially across compounds.

Compounded peptide preparations operate under the FDA Compounding Quality Act of 2013 without FDA pre-market approval. The evidence base for compounded peptide preparations varies substantially across compounds. Some compounded peptides operate at L3 human trials evidence tier with international approval contexts. Other compounded peptides operate at L1 to L2 evidence tier with primarily preclinical evidence. PSI provides conceptual education only. PSI does not provide personalized clinical recommendations, dosing guidance, or self-administration instructions. Clinical practice decisions must be made by a qualified physician evaluating individual patient context. Specialty coordination supports complex contexts. Patient-specific factors including age, sex, comorbidities, concurrent medications, and indication match all affect clinical decisions. The PSI physician directory provides verified physicians applying FDA prescribing information and AMA Code 1.1.5 framework to peptide therapy clinical decisions.

Assessment

Peptide therapy operates within the established clinical practice framework with physician-directed protocols across FDA-approved and compounded preparations.

PSI's reading: peptide therapy operates within the established clinical practice framework with physician-directed protocols. The FDA-approved peptide drug class is a legitimate therapeutic class with completed FDA pre-market review and ongoing post-marketing surveillance through FDA MedWatch. The compounded peptide preparation category operates within the AMA Code of Medical Ethics 1.1.5 framework with physician-determined protocols per documented risk-benefit assessment. The PSI four-tier evidence framework supports transparent claim communication across compounds with varying evidence quality. Every compound on PSI declares one locked evidence level traceable to PubMed-indexed peer-reviewed primary sources. The four-stage monitoring cadence applies across the class. Specialty coordination supports complex contexts across multiple medical specialties. The PSI physician directory provides verified physicians applying FDA prescribing information, AMA Code 1.1.5 framework, and society Clinical Practice Guidelines to peptide therapy clinical decisions.

How to Approach Your Decision

Limitations and Caveats

This page is conceptual education only. PSI does not provide personalized clinical recommendations, dosing guidance, or self-administration instructions.
Peptide therapy clinical practice is physician-directed. Discuss specific peptide therapy with your prescribing physician.
FDA-approved class differs from compounded preparations. Distinct regulatory frameworks apply.
Compounded peptide preparation evidence varies substantially. Some compounds operate at L3 human trials tier, others at L1 to L2 preclinical or animal studies tier.
Patient-specific clinical context affects decisions. Age, sex, comorbidities, concurrent medications, and indication match all matter.
Specialty coordination supports complex contexts. Multiple medical specialties may be involved in individual cases.
Cardiovascular boxed warnings affect framework for specific compounds. Evenity romosozumab requires cardiology coordination per ARCH trial findings.
Self-sourcing of peptide preparations operates outside the validated clinical practice framework. Research-grade products are not a legal substitute for physician-prescribed therapy.

What's Marketed vs What's Studied

7 common claims, corrected.

“Peptides and anabolic steroids are the same thing.”

Peptides and anabolic steroids represent distinct molecular classes. Peptides are short amino acid chains that function as signaling molecules through receptor binding. Anabolic steroids are synthetic hormones structurally related to testosterone with direct hormone replacement or amplification. Anabolic steroids operate under Schedule III controlled substance classification. PSI documents peptide therapy. PSI does not document anabolic steroid use.

“All peptides used in clinical practice are FDA-approved.”

Peptides operate in both FDA-approved and compounded categories. The FDA-approved class spans GLP-1 receptor agonists, anabolic osteoporosis peptides, growth hormone secretagogue, and sexual health peptides. Compounded peptide preparations operate under FDA Compounding Quality Act of 2013 with AMA Code 1.1.5 framework. Both categories operate within the legitimate clinical practice framework.

“Compounded peptide preparations are unregulated.”

Compounded peptide preparations operate under the FDA Compounding Quality Act of 2013. 503A traditional compounding pharmacies and 503B outsourcing facilities operate under FDA and state pharmacy board oversight. PCAB accreditation, USP General Chapter 797, and USP General Chapter 800 standards apply. AMA Code of Medical Ethics 1.1.5 framework governs the prescribing decision.

“Peptide therapy is a single uniform therapeutic class.”

Peptide therapy spans multiple distinct classes including GLP-1 receptor agonists for chronic weight management and type 2 diabetes, anabolic osteoporosis peptides for postmenopausal osteoporosis, growth hormone secretagogue for HIV-associated lipodystrophy, sexual health peptides, and others. Each class has distinct mechanisms, indications, evidence base, and clinical framework.

“PSI provides personalized peptide therapy recommendations.”

PSI provides conceptual education only and does not provide personalized clinical recommendations, dosing guidance, or self-administration instructions. Clinical practice decisions must be made by a qualified physician evaluating individual patient context. The PSI physician directory provides verified physicians with peptide therapy experience.

“International peptide approvals are equivalent to FDA approval.”

International approvals do not equal FDA approval. Examples include thymosin alpha-1 with international Zadaxin approval in approximately 35 countries which is classified at L3 human trials evidence tier per PSI framework rather than L4 FDA-approved. L4 requires US FDA pre-market review per 21 CFR 314.

“Self-sourcing peptide preparations is equivalent to physician-prescribed therapy.”

Self-sourcing of peptide preparations outside physician prescribing pathways operates outside the validated clinical practice framework. Research-grade peptide products labeled not for human use are not a legal substitute for physician-prescribed FDA-approved or compounded therapy. Self-administration without physician instruction operates outside AMA Code 1.1.5 framework.

Common Questions

What is peptide therapy?

Peptide therapy uses short chains of amino acids as signaling molecules to influence biological pathways. The FDA-approved peptide drug class spans GLP-1 receptor agonists, anabolic osteoporosis peptides, growth hormone secretagogue, and sexual health peptides. Compounded peptide preparations operate under AMA Code of Medical Ethics 1.1.5 framework.

How do peptides work in the body?

Peptides bind to specific cellular receptors triggering downstream signaling cascades. Examples include the GLP-1 receptor pathway (semaglutide, tirzepatide), parathyroid hormone receptor pathway (teriparatide, abaloparatide), Wnt signaling via sclerostin antibody (romosozumab), growth hormone secretagogue receptor pathway (Tesamorelin), and melanocortin receptor pathway (bremelanotide).

Are peptides the same as steroids?

No. Peptides and anabolic steroids represent distinct molecular classes. Peptides are short amino acid chains that function as signaling molecules through receptor binding. Anabolic steroids are synthetic hormones structurally related to testosterone with direct hormone replacement. Anabolic steroids operate under Schedule III controlled substance classification.

Is peptide therapy FDA-approved?

The FDA-approved peptide drug class spans multiple indications. Examples include semaglutide (Wegovy NDA 215256, Ozempic NDA 209637), tirzepatide (Zepbound NDA 217806, Mounjaro NDA 215866), teriparatide (Forteo NDA 021318), abaloparatide (Tymlos NDA 208743), romosozumab (Evenity NDA 761062 with CV boxed warning), Tesamorelin Egrifta (NDA 022505), and Vyleesi bremelanotide (NDA 210557). Many other peptides operate as compounded preparations under AMA Code 1.1.5 framework.

Who can prescribe peptide therapy?

Licensed physicians (MDs or DOs) prescribe peptide therapy. Specialty coordination spans primary care, endocrinology, weight medicine, rheumatology, sports medicine, immunology, infectious disease, women's health, men's health, and cardiology for cardiovascular boxed warning contexts. State medical board licensure and ABMS board certification anchor the verification framework.

What is the FDA Compounding Quality Act of 2013?

The FDA Compounding Quality Act of 2013 (Drug Quality and Security Act) governs pharmacy compounding in the United States. The framework distinguishes 503A traditional compounding pharmacies preparing patient-specific preparations per physician prescription from 503B outsourcing facilities preparing larger batches under FDA registration with adherence to cGMP standards.

What is AMA Code of Medical Ethics 1.1.5?

AMA Code of Medical Ethics Opinion 1.1.5 (Off-Label and Investigational Use of Pharmaceuticals) governs off-label and compounded prescribing decisions. The framework requires documented risk-benefit assessment for the specific patient context, FDA-approved alternatives considered per indication, monitoring requirements, and patient understanding through informed consent acknowledgment.

What is the PSI four-tier evidence framework?

PSI uses a four-tier evidence framework distinguishing preclinical (L1), animal studies (L2), human trials (L3), and FDA-approved (L4) compounds. Visitor-facing labels are FDA Approved, Human Trials, Animal Studies, and Preclinical. Every compound on PSI declares one locked evidence level traceable to PubMed-indexed peer-reviewed primary sources.

What conditions does peptide therapy treat?

FDA-approved peptide therapy treats chronic weight management (semaglutide, tirzepatide, liraglutide), type 2 diabetes (semaglutide, tirzepatide), postmenopausal osteoporosis with high fracture risk (teriparatide, abaloparatide, romosozumab), HIV-associated lipodystrophy (Tesamorelin), and HSDD in premenopausal women (bremelanotide). Compounded peptide preparations operate across additional indications under AMA Code 1.1.5 framework.

How is peptide therapy administered?

FDA-approved peptide drugs use three primary injection routes per FDA prescribing information. Subcutaneous administration is the most common. Intramuscular and intravenous routes apply for specific indications. The physician determines route, dose, and schedule per FDA label. See Injection Protocols 101 for the framework.

What is the four-stage monitoring cadence?

The four-stage monitoring cadence applies across peptide therapy. Stage 1 baseline at week 0. Stage 2 early follow-up at week 4 to 8. Stage 3 stabilization at month 3. Stage 4 maintenance at month 6 with annual continuation thereafter. Indication-specific markers re-checked at each stage.

What are common side effects of FDA-approved peptide therapy?

Side effects vary by peptide class per FDA prescribing information. GLP-1 receptor agonists commonly cause gastrointestinal effects including nausea and constipation. Anabolic osteoporosis peptides may cause injection site reactions. Evenity carries a cardiovascular boxed warning. The physician discusses specific safety framework per FDA label. See Peptide Therapy Safety for the framework.

Can patients administer peptide injections at home?

Patient-administered subcutaneous injections require physician or pharmacist instruction including site selection, injection technique, needle handling, sharps disposal, and rotation principles. Patient administration without physician instruction operates outside the validated clinical practice framework. PSI does not provide administration instruction.

What is the difference between FDA-approved and compounded peptide therapy?

FDA-approved peptide drugs operate under FDA pre-market review with prescribing information. Compounded peptide preparations operate under FDA Compounding Quality Act of 2013 without pre-market approval, with physician-directed protocols per AMA Code 1.1.5 framework. See Compounded vs FDA-Approved Peptides for the framework.

Where can I find a peptide therapy physician?

The PSI physician directory provides verified physicians across major US cities with peptide therapy experience. Verification includes state medical board license verification, ABMS board certification, and AMA Code 1.1.5 documentation practice. See Finding a Peptide Doctor for the directory.

Does PSI provide medical advice about peptide therapy?

No. PSI provides conceptual education only and does not provide personalized clinical recommendations, dosing guidance, or self-administration instructions. Clinical practice decisions must be made by a qualified physician evaluating individual patient context. PSI provides historical and methodology reference to inform discussion with prescribing physicians.

Sourcing Checklist

Obtain peptide therapy through licensed physician prescription with documented clinical evaluation.
Self-sourcing of peptide preparations outside physician prescribing pathways operates outside the validated clinical practice framework. Research-grade peptide products are not a legal substitute.
Verify physician credentials including state medical board license and ABMS board certification.
State pharmacy board license verification, ABMS board certification, and AMA Code 1.1.5 documentation practice anchor verification. PSI physician directory provides verified credentials.
Expect FDA prescribing information framework for FDA-approved peptide drugs.
FDA-approved peptide drugs operate under FDA prescribing information per 21 CFR 314 with completed FDA pre-market review including Phase 1, Phase 2, and Phase 3 trial evidence.
Expect AMA Code 1.1.5 framework documentation for compounded preparations.
Documentation includes risk-benefit assessment, FDA-approved alternatives considered, monitoring requirements, and patient understanding through informed consent acknowledgment.
Confirm 503A pharmacy or 503B outsourcing facility for compounded preparation sourcing.
503A traditional compounding pharmacies prepare patient-specific preparations. 503B outsourcing facilities prepare larger batches under FDA registration. PCAB accreditation supports verification.
Expect baseline labs and four-stage monitoring cadence framework.
Stage 1 baseline week 0, Stage 2 early follow-up week 4-8, Stage 3 stabilization month 3, Stage 4 maintenance month 6 with annual continuation thereafter.
Report serious adverse events through FDA MedWatch surveillance.
FDA MedWatch supports serious adverse event reporting for FDA-approved peptide drug class supporting ongoing safety signal monitoring.
Verify evidence-tier classification per PSI four-tier framework.
L1 preclinical, L2 animal studies, L3 human trials (including international approvals), L4 FDA-approved. Visitor labels: FDA Approved, Human Trials, Animal Studies, Preclinical.
Expect specialty coordination for indication-specific contexts.
Specialty coordination spans primary care, endocrinology, weight medicine, rheumatology, sports medicine, immunology, infectious disease, women's health, men's health, and cardiology.

Regulatory Context

The peptide therapy regulatory landscape continues to evolve. New FDA approvals expand the FDA-approved peptide drug class. New compounded preparation contexts emerge as patient-specific clinical needs evolve. AMA Code of Medical Ethics 1.1.5 framework remains foundational. Society Clinical Practice Guidelines update on multi-year cycles including AACE/ACE Postmenopausal Osteoporosis CPG, Endocrine Society CPG, and ADA Standards of Care. PSI tracks regulatory updates and new peer-reviewed primary sources per the Editorial Standards review cadence.

Comparison

Peptide Class	Indication	FDA-Approved Examples	Evidence Anchor
GLP-1 receptor agonist	Chronic weight management	Wegovy NDA 215256, Zepbound NDA 217806, Saxenda	SELECT 2023, SURMOUNT-1 2022
GLP-1 receptor agonist	Type 2 diabetes	Ozempic NDA 209637, Mounjaro NDA 215866, Victoza	SUSTAIN-6 2016, LEADER 2016
Anabolic osteoporosis (PTH analog)	Postmenopausal osteoporosis high fracture risk	Forteo NDA 021318, Tymlos NDA 208743	VERT 2001, ACTIVE 2016
Sclerostin antibody	Postmenopausal osteoporosis high fracture risk	Evenity NDA 761062 with CV boxed warning	FRAME 2016, ARCH 2017
Growth hormone secretagogue	HIV-associated lipodystrophy	Tesamorelin Egrifta NDA 022505	LIPO Phase 3 program
Sexual health (melanocortin)	HSDD in premenopausal women	Vyleesi bremelanotide NDA 210557	RECONNECT Phase 3 program
Compounded peptide preparation	Various per indication	Per AMA Code 1.1.5 framework	Variable evidence tier L1 to L3

Who This Applies To

· Patient researching peptide therapy at the universal-awareness level.
· Adult considering FDA-approved peptide therapy for chronic weight management.
· Adult considering FDA-approved peptide therapy for type 2 diabetes.
· Postmenopausal woman considering anabolic osteoporosis peptide therapy for high fracture risk.
· Patient seeking the difference between FDA-approved and compounded peptide therapy.
· Patient evaluating evidence-tier classification across peptide compounds.
· Adult considering compounded peptide therapy and reviewing AMA Code 1.1.5 framework.
· Patient seeking specialty coordination framework for peptide therapy clinical context.
· Researcher reviewing the peptide therapy regulatory landscape.
· Adult preparing for peptide therapy consultation with a prescribing physician.

Verdict

Peptide therapy uses short chains of amino acids as signaling molecules to influence biological pathways. The FDA-approved peptide drug class spans multiple indications including chronic weight management, type 2 diabetes, postmenopausal osteoporosis, HIV-associated lipodystrophy, and HSDD. Compounded peptide preparations operate under AMA Code 1.1.5 framework. The PSI four-tier evidence framework provides transparent classification. Clinical practice decisions must be made by a qualified physician.

In Plain Terms

Peptide therapy uses short chains of amino acids that signal cells in your body. FDA-approved peptides treat several conditions including weight loss, diabetes, osteoporosis, and others. Examples include Wegovy, Ozempic, Zepbound, Mounjaro, Forteo, Tymlos, and Evenity. Other peptides come from compounding pharmacies. Your doctor decides which peptide is right for you based on FDA labels and your situation. PSI does not give medical advice. Always work with a licensed physician.

Peptide therapy means using small protein-like molecules to signal your body. Some peptides are FDA-approved drugs like Wegovy and Forteo. Others come from compounding pharmacies. Different peptides do different things. Your doctor picks the right one for your situation. Always work with a licensed physician for peptide therapy decisions.

Peptide therapy clinical practice requires physician evaluation. The PSI physician directory provides verified physicians applying FDA prescribing information and AMA Code 1.1.5 framework to peptide therapy clinical decisions across primary care, endocrinology, weight medicine, rheumatology, sports medicine, immunology, infectious disease, women's health, men's health, and cardiology specialties.

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PSI's directory only lists physicians who have passed a five-gate verification process: state board active, no disciplinary actions, peptide-category competency, transparent pricing, and patient outcome documentation.

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Featured Compounds

Common Contexts

· Patient researching peptide therapy awareness level
· Adult considering FDA-approved peptide therapy for weight management
· Adult considering FDA-approved peptide therapy for type 2 diabetes
· Postmenopausal woman considering anabolic osteoporosis peptide
· Patient seeking FDA-approved vs compounded distinction
· Patient evaluating evidence-tier classification framework
· Adult considering compounded peptide therapy AMA Code 1.1.5
· Patient seeking specialty coordination framework
· Researcher reviewing peptide therapy regulatory landscape
· Adult preparing for peptide therapy consultation

Important Context

This page is educational and does not constitute medical advice. The information presented reflects FDA prescribing information for FDA-approved peptide drugs (Wegovy NDA 215256, Ozempic NDA 209637, Zepbound NDA 217806, Mounjaro NDA 215866, Forteo NDA 021318, Tymlos NDA 208743, Evenity NDA 761062 with cardiovascular boxed warning, Tesamorelin Egrifta NDA 022505, Vyleesi NDA 210557), society Clinical Practice Guidelines (AACE/ACE 2020 Postmenopausal Osteoporosis CPG, Endocrine Society 2019 CPG, ADA 2024 Standards of Care), AMA Code of Medical Ethics 1.1.5 (Off-Label and Investigational Use of Pharmaceuticals) and 2.1.1 (Informed Consent) frameworks, FDA Compounding Quality Act of 2013, and cardiovascular outcomes trial evidence including SELECT 2023, SUSTAIN-6, LEADER, VERT, ACTIVE, FRAME, and ARCH. This page provides conceptual education only and does not provide personalized clinical recommendations.

Your physician will evaluate any peptide therapy decision in the context of your individual clinical situation. The framework described here is general and does not substitute for individualized clinical judgment. Specialty coordination supports complex contexts across primary care, endocrinology, weight medicine, rheumatology, sports medicine, immunology, infectious disease, women's health, men's health, and cardiology.

Conceptual education does not substitute for prescribing physician evaluation and clinical oversight. Self-sourcing of peptide preparations outside physician prescribing pathways operates outside the validated clinical practice framework. Research-grade peptide products labeled not for human use are not a legal substitute for physician-prescribed FDA-approved or compounded therapy.

Educational content only. This page provides conceptual education about peptide therapy at the universal-awareness level. PSI does not provide personalized clinical recommendations, dosing guidance, or self-administration instructions. Clinical practice decisions should be made by a qualified physician who can evaluate your individual situation. Discuss with your physician before initiating any peptide therapy.

Sources and Citations

[1] FDA Prescribing Information: Wegovy (semaglutide) injection · 2024 · FDA NDA 215256 · Source
[2] FDA Prescribing Information: Ozempic (semaglutide) injection · 2024 · FDA NDA 209637 · Source
[3] FDA Prescribing Information: Zepbound (tirzepatide) injection · 2024 · FDA NDA 217806 · Source
[4] FDA Prescribing Information: Forteo (teriparatide) injection · 2020 · FDA NDA 021318 · Source
[5] FDA Prescribing Information: Evenity (romosozumab-aqqg) with cardiovascular boxed warning · 2019 · FDA NDA 761062 · Source
[6] Lincoff AM, Brown-Frandsen K, Colhoun HM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (SELECT trial) · New England Journal of Medicine · 2023 · DOI
[7] Marso SP, Bain SC, Consoli A, et al. Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes (SUSTAIN-6) · New England Journal of Medicine · 2016 · DOI
[8] Neer RM, Arnaud CD, Zanchetta JR, et al. Effect of Parathyroid Hormone (1-34) on Fractures and Bone Mineral Density in Postmenopausal Women with Osteoporosis (VERT trial) · New England Journal of Medicine · 2001 · DOI
[9] Saag KG, Petersen J, Brandi ML, et al. Romosozumab or Alendronate for Fracture Prevention in Women with Osteoporosis (ARCH trial) · New England Journal of Medicine · 2017 · DOI
[10] American Diabetes Association. Standards of Care in Diabetes 2024 · Diabetes Care · 2024 · DOI
[11] Camacho PM, Petak SM, Binkley N, et al. AACE/ACE Clinical Practice Guidelines for the Diagnosis and Treatment of Postmenopausal Osteoporosis 2020 Update · Endocrine Practice · 2020 · DOI
[12] AMA Code of Medical Ethics Opinion 1.1.5: Off-label and Investigational Use of Pharmaceuticals · American Medical Association · 2024 · Source

Medical Disclaimer

This content is for educational and informational purposes only and does not constitute medical advice. The information presented reflects published research as indexed by PSI and should not be used to make treatment decisions. Always consult a qualified healthcare provider before starting, stopping, or modifying any treatment.